Best Management Practices Before Construction

Storm Drain Inlet Protection

There are several storm drain inlet protection products available for use which include inlet protection pillows, bags, and straw wattles.

They should be placed adjacent to and in the flow path to all existing catch basins and curb inlets in the vicinity of the project.

The bags need to be checked after every significant rain event to determine if sediment is getting around the bags and into the inlet. Sediment trapped by the bags needs to be removed, and the bags replaced after any significant accumulation.

Gravel Construction Entrances

Gravel construction entrances reduce the amount of mud and dirt tracked onto streets by running vehicles over a gravel pad prior to leaving the work site.

The gravel pad should be the full width of the ingress and egress area, extend to the structure and should be a minimum of 4 inches deep.

Larger rock (2-1/2 inches or greater) works best and additional rock should be added periodically to maintain a clean surface.

Silt Fences

Silt fences are designed to intercept and detain sediment before it leaves the site by being installed on the downhill side of any disturbed area and where runoff can leave the property, and at the toe of stockpiles.

Silt fences must be trenched and back filled at least 6 inches into the ground on the down stream on the back of the slope, and stretched tight between the posts.

More than one row of silt fencing may be required and sediment must be removed when it reaches one-third the height of the fence.

Undisturbed Buffer Zone

Adjacent undisturbed land where existing vegetation can remain as a buffer zone can act as a natural filter to reduce soil erosion and runoff velocities. The buffer zone must be a grassy area covered with dense vegetation. These buffer zones can be used to supplement silt fences and should be identified as buffer areas with stakes and fencing to prevent equipment or vehicle entry.